In the course of railway reforms in the end of the last century, national European governments, as well the EU Commission, decided to open markets and to separate railway networks from train operations. Vertically integrated railway companies - companies owning a network and providing transport services - argue that such a separation of infrastructure and operations would diminish the advantages of vertical integration and would therefore not be suitable to raise economic welfare. In this paper, we conduct a pan-European analysis to investigate the performance of European railways with a particular focus on economies of vertical integration. We test the hypothesis that integrated railways realise economies of joint production and, thus, produce railway services on a higher level of efficiency. To determine whether joint or separate production is more efficient we apply a Data Envelopment Analysis super-efficiency bootstrapping model which relates the efficiency for integrated production to a virtual reference set consisting of the separated production technology. Our findings are that in a majority of European Railway companies exist economies of scope.